Generally, planetary transmissions include a plurality of planetary gear trains that are shifted using friction elements and/or control elements, such as brakes and clutches. For many years, most industrial transmissions were fractionated transmissions composed of two, two degree of freedom gearboxes in series. Such arrangements can be relatively large and cumbersome in order to meet the performance and speed criterion for practical use in industrial applications.
More recently, numerous more compact, multispeed transmissions have been proposed and are in use. For example, U.S. Patent Publication 2008/0108472 A1 to Seo, et al., proposed a planetary transmission with four gear trains, three clutches and four brakes, to provide a four-degree of freedom transmission with seven forward speeds and two reverse speeds. It remains desirable, however, to provide a compact planetary gearing arrangement that includes a minimum number of components that meets the performance criterion for use in industrial applications.